Support for multiple FFmpeg versions.

--- ffmpeg-8.1.3/configure.orig
+++ ffmpeg-8.1.3/configure
@@ -4432,7 +4432,7 @@
 SLIBNAME_WITH_MAJOR='$(SLIBNAME).$(LIBMAJOR)'
 LIB_INSTALL_EXTRA_CMD='$$(RANLIB) "$(LIBDIR)/$(LIBNAME)"'
 SLIB_INSTALL_NAME='$(SLIBNAME_WITH_VERSION)'
-SLIB_INSTALL_LINKS='$(SLIBNAME_WITH_MAJOR) $(SLIBNAME)'
+SLIB_INSTALL_LINKS='$(SLIBNAME_WITH_MAJOR) $(SLIBPREF)$(FULLNAME)8$(SLIBSUF)'
 VERSION_SCRIPT_POSTPROCESS_CMD="cat"
 
 asflags_filter=echo
--- ffmpeg-8.1.3/ffbuild/pkgconfig_generate.sh.orig
+++ ffmpeg-8.1.3/ffbuild/pkgconfig_generate.sh
@@ -38,7 +38,7 @@
 Requires: $($shared || echo $requires)
 Requires.private: $($shared && echo $requires)
 Conflicts:
-Libs: -L\${libdir} $rpath -l${fullname#lib} $($shared || echo $libs)
+Libs: -L\${libdir} $rpath -l${fullname#lib}8 $($shared || echo $libs)
 Libs.private: $($shared && echo $libs)
 Cflags: -I\${includedir}
 EOF